新课标要求我们在教学中注重思维能力的培养,注重数学思想方法渗透,而求代数式的值是初中数学最基本的训练方法,也是近年来中考和数学竞赛中的必考内容,求代数式的值的一般步骤是先代入,再计算求值。但在实际解题时,常常需要综合运用知识求值。下面结合笔者多年教学实践经验谈 The new curriculum requires that we pay attention to the cultivation of thinking ability in teaching, pay attention to the penetration of mathematical thinking methods, and the value of algebraic mathematics is the most basic training methods, but also in recent years in the middle school entrance examination and mathematics contest content, algebraic The general steps of value are to first substitute and then calculate the value. However, in actual problem solving, it is often necessary to evaluate knowledge synthetically. The following combination of my years of teaching experience in practice